Pharmacokinetics and pharmacodynamics of p-aminopropiophenone in rabbits

Original Article

Pharmacokinetics and pharmacodynamics of p-aminopropiophenone in rabbits

Authors:
Lan-Ting Liu,
Ru-Heng Huang

Abstract

As a methemoglobin former. p-aminopropiophenone (PAPP) has been used for anticyanide poisoning recently. After im PAPP 10 mg/kg, the blood drug level and methemoglobin in rabbits were estimated by phosphorimetric and photometric method, respectively. PAPP was a two compartment open model drug and the effective antipoisoning time was relatively long (ca 20 min). The peak concentration time of methemoglobin (ca 30 min) was later than that of PAPP (ca lO min). After 30 min, the linear relationship between blood drug concentration and MetHb was observed according to the following equation: In (MetHb %) =3.836+1.191 Ln C The amount of MetHb was calculated from the blood drug concentration by the above equation. The phamarcokinetic model of PAPP in sodium cyanide poisoned animals was changed into one-compartment open model. The blood drug concentration, AUC, and t1/2 were lower than those of the controls (not poisoned with sodium cyanide). The concentration of MetHb formed in poisoned rabbits was higher than that in the control. The results indicated that sodium cyanide affects the pharmacodynamics of PAPP (the time course of methemoglobin formation).